MC68HC705J MOTOROLA [Motorola, Inc], MC68HC705J Datasheet - Page 38

• Manufacturer Part Number: MC68HC705J
• Description: Microcontrollers
• Manufacturer: MOTOROLA [Motorola, Inc]

Memory
2.6 EPROM/OTPROM
2.6.1 EPROM/OTPROM Programming
Technical Data
38
NOTE:
A microcontroller unit (MCU) with a quartz window has 1240 bytes of
erasable, programmable ROM (EPROM). The quartz window allows
EPROM erasure with ultraviolet light.
Keep the quartz window covered with an opaque material except when
programming the MCU. Ambient light can affect MCU operation.
In an MCU without the quartz window, the EPROM cannot be erased
and serves as 1240 bytes of one-time programmable ROM (OTPROM).
These addresses are user EPROM/OTPROM locations:
The computer operating properly (COP) register (COPR) is an
EPROM/OTPROM location at address $07F0.
The mask option register (MOR) is an EPROM/OTPROM location at
address $07F1.
The two ways to program the EPROM/OTPROM are:
1. Manipulating the control bits in the EPROM programming register
2. Programming the EPROM/OTPROM with the M68HC705J
•
•
$0300–$07CF
$07F8–$07FF, used for user-defined interrupt and reset vectors
to program the EPROM/OTPROM on a byte-by-byte basis
in-circuit simulator (M68HC705JICS) available from Motorola
Memory
MC68HC705J1A — Rev. 4.0
MOTOROLA